bool
OcclusionQueryNode::getPassed( const osg::Camera* camera, float distanceToEyePoint )
{
if ( !_enabled )
// Queries are not enabled. The caller should be osgUtil::CullVisitor,
// return true to traverse the subgraphs.
return true;
// In the future, we could hold a reference directly to the QueryDrawable
// to avoid the dynamic_cast.
QueryGeometry* qg = dynamic_cast< QueryGeometry* >( _queryGeode->getDrawable( 0 ) );
if (qg == NULL)
{
osg::notify( osg::FATAL ) <<
"osgOQ: OcclusionQueryNode: No QueryGeometry." << std::endl;
// Something's broke. Return true so we at least render correctly.
return true;
}
// If the distance to the bounding sphere shell is positive, retrieve
// the results. Others (we're inside the BS shell) we are considered
// to have passed and don't need to retrieve the query.
const osg::BoundingSphere& bs = getBound();
float distance = distanceToEyePoint - bs._radius;
_passed = ( distance <= 0.f );
if (!_passed)
{
int result = qg->getNumPixels( camera );
_passed = ( (unsigned int)(result) > _visThreshold );
}
return _passed;
}
bool OcclusionQueryNode::getPassed( const Camera* camera, NodeVisitor& nv )
{
if ( !_enabled )
// Queries are not enabled. The caller should be osgUtil::CullVisitor,
// return true to traverse the subgraphs.
return true;
{
// Two situations where we want to simply do a regular traversal:
// 1) it's the first frame for this camera
// 2) we haven't rendered for an abnormally long time (probably because we're an out-of-range LOD child)
// In these cases, assume we're visible to avoid blinking.
OpenThreads::ScopedLock<OpenThreads::Mutex> lock( _frameCountMutex );
const unsigned int& lastQueryFrame( _frameCountMap[ camera ] );
if( ( lastQueryFrame == 0 ) ||
( (nv.getTraversalNumber() - lastQueryFrame) > (_queryFrameCount + 1) ) )
return true;
}
if (_queryGeode->getDrawable( 0 ) == NULL)
{
OSG_FATAL << "osgOQ: OcclusionQueryNode: No QueryGeometry." << std::endl;
// Something's broke. Return true so we at least render correctly.
return true;
}
QueryGeometry* qg = static_cast< QueryGeometry* >( _queryGeode->getDrawable( 0 ) );
// Get the near plane for the upcoming distance calculation.
float nearPlane;
const osg::Matrix& proj( camera->getProjectionMatrix() );
if( ( proj(3,3) != 1. ) || ( proj(2,3) != 0. ) || ( proj(1,3) != 0. ) || ( proj(0,3) != 0.) )
nearPlane = proj(3,2) / (proj(2,2)-1.); // frustum / perspective
else
nearPlane = (proj(3,2)+1.) / proj(2,2); // ortho
// If the distance from the near plane to the bounding sphere shell is positive, retrieve
// the results. Otherwise (near plane inside the BS shell) we are considered
// to have passed and don't need to retrieve the query.
const osg::BoundingSphere& bs = getBound();
float distanceToEyePoint = nv.getDistanceToEyePoint( bs._center, false );
float distance = distanceToEyePoint - nearPlane - bs._radius;
_passed = ( distance <= 0.f );
if (!_passed)
{
int result = qg->getNumPixels( camera );
_passed = ( (unsigned int)(result) > _visThreshold );
}
return _passed;
}